In 1979 the Division of Parasitic Diseases (DPD/NCID/CDC) established research collaboration with the Kenya Medical Research Institute (KEMRI) in Kenya. KEMR! is an organization of the Kenyan Ministry of Health, and is responsible for conducting research into the major public health problems of the country. During the ensuing 26 years, this collaboration has evolved into the KEMRI/CDC Field Station, which has become a major installation in Nyanza Province in western Kenya with substantial infrastructure and human resource capacity. The KEMRI/CDC Field Station is located near the city of Kisumu next to Lake Victoria on the campus of the KEMRI Center for Vector Biology Control and Research (CVBCR). The Field Station is one of the four major elements of CDC Kenya; the other three are headquartered in Nairobi and include the Global AIDS Program (GAP), the International Emerging Infections Program (IEIP), and the Polio Eradication/Measles Elimination Program. For the latter activity, CDC staff is seconded to the WHO Regional office in Nairobi. The-mission of the KEMRI/CDC Field Station is to promote public health in Kenya and East Africa through collaborative research, training, control and prevention activities. There is an urgent need to address the pressing public health needs of Kenya and the eastern Africa region. The Field Station is located in an area of western Kenya where P. falciparum malaria and HIV are major public health problems. It is estimated that globally, approximately 300-500 million persons suffer from malaria each year, resulting in approximately one million deaths. Each year in Kenya, malaria accounts for 8 million-outpatient visits and the deaths of approximately 26,000 children under age 5. In western Kenya near Lake Victoria, malaria transmission is intense; on average, each inhabitant in this area receives about 100-300 infective mosquito bites per year. Antimaiarial drug resistance is widespread, rendering most treatment with standard medications such as chloroquine and sulphadoxine-pyrimethamine ineffective, and highlighting the need to explore and evaluate new prevention strategies and therapies for case management. HIV has also had a devastating impact on Kenya. The overall national HIV infection prevalence among adults is estimated at approximately 7%, resulting in approximately 1.1 million HIV-infected Kenyans. Infection prevalence is highest in Nyanza Province (14%) where the Field Station is located; approximately one-third of all HIV-infected Kenyans live in this Province. In some groups such as pregnant women attending antenatal clinics, HIV infection prevalence rates of 30-40% have been observed in Nyanza. Other infectious diseases also exert an enormous toll in Kenya. Diarrhea! diseases appear to be responsible for about a quarter of all infant deaths, and safe drinking water is not yet generally available. Pneumonia is also responsible for one-quarter to one third of deaths in young children. Furthermore, tuberculosis incidence, fueled by the ongoing HIV epidemic, has increased six-fold in Kenya during the 1990s; in 2004 over 100,000 cases were reported. In Nyanza Province alone, 17,000 cases were reported in 2003 (1.5 times the number reported in the entire U.S. during the same year). Schistosomiasis (Schistosoma mansoni) is also endemic along the shores of Lake Victoria. Since 2000, in response to these national, regional and global health challenges, the Field Station has expanded its mission and staff. Before this time, most activities focused on the major public health problem of malaria. Although malaria remains one of the priorities, HIV research supported by the Division of HIV/AIDS Prevention (DHAP/NCHSTP) and HIV prevention and care program activities supported by the Global AIDS Program (GAP/NCHSTP) are also now a primary focus. Two full-time HIV research epidemiologists and a PHA as well as other senior scientists supported by GAP have recently been assigned to the Field Station. In 2002 NCID/CDC selected Kenya as the site for a CDC International Emerging Infections Program (IEIP), joining the IEIP in Thailand as the first two of what will eventually become a global network of centers of excellence in emerging infectious disease surveillance, research, outbreak response and training. The lEIPs are a collaborative effort between CDC and the host country MOH. As part of the Kenya IEIP training component, a Field Epidemiology and Training Program (FELTP) has recently been established. The FELTP is a two-year program leading to a Masters degree in applied epidemiology or public health laboratory management. The KEMRI/CDC Field Station is well positioned to fulfill its mission to promote public health in Kenya and East Africa through collaborative research, training, control and prevention activities. Through collaborative efforts, KEMRI and CDC together can make important contributions to global surveillance to monitor HIV, malaria, and other emerging and re-emerging infectious diseases, assess problems of public health importance such as the spread of antimicrobial resistance, and provide a basis for evaluating interventions designed to reduce the burden of disease among vulnerable groups. The strong and wellestablished relationships with KEMRI, the Kenya Ministry of Health, and the United States Embassy in Nairobi provide a receptive environment for the activities described herein.